public class Demo3 {
	static int i = 10;
	int j;
	Demo3() {
		this.j = 20;
	}

	public static void main(String[] args) {
		System.out.println("类变量 i=" + Demo3.i);
		Demo3 obj = new Demo3();
		System.out.println("实例变量 j=" + obj.j);
	}
}
